Characteristic |
Overall |
Age Categories at Birth |
|||
|---|---|---|---|---|---|
≤ 27 Weeks |
28-32 Weeks |
33-36 Weeks |
≥36 Weeks |
||
| Number of Patients (N) | 524 | 49 | 116 | 123 | 236 |
| Post-Menstrual Age at Birth in Weeks (Median (IQR)) | 36.1 (31.4, 38.4) | 26.0 (24.7, 26.6) | 30.1 (28.7, 31.6) | 35.3 (34.0, 36.0) | 38.7 (38.0, 40.0) |
| Male Sex (N (%)) | 440 (84%) | 45 (92%) | 97 (84%) | 105 (85%) | 193 (82%) |
| Weight at Birth in Grams (Median (IQR)) | 2,140 (1,159, 2,998) | 731 (600, 910) | 1,203 (935, 1,650) | 2,108 (1,800, 2,520) | 3,140 (2,600, 3,450) |
| Location Prior to Day of Surgery | |||||
| Home/Residential Care | 353 (68%) | 12 (25%) | 60 (52%) | 89 (73%) | 192 (82%) |
| Hospital Ward | 63 (12%) | 4 (8.3%) | 12 (10%) | 17 (14%) | 30 (13%) |
| NICU | 46 (8.9%) | 20 (42%) | 20 (17%) | 4 (3.3%) | 2 (0.9%) |
| PICU | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Special Care Nursery | 26 (5.0%) | 6 (13%) | 15 (13%) | 5 (4.1%) | 0 (0%) |
| Other Health Care Facility | 31 (6.0%) | 6 (13%) | 9 (7.8%) | 7 (5.7%) | 9 (3.9%) |
| Respiratory Support Prior to Surgery | |||||
| LFNP | 37 (76%) | 20 (74%) | 13 (76%) | 3 (75%) | 1 (100%) |
| HFNP | 6 (12%) | 2 (7.4%) | 3 (18%) | 1 (25%) | 0 (0%) |
| NIV | 1 (2.0%) | 0 (0%) | 1 (5.9%) | 0 (0%) | 0 (0%) |
| ETT | 5 (10%) | 5 (19%) | 0 (0%) | 0 (0%) | 0 (0%) |
| NICU Admission Between Birth & Surgery | 238 (46%) | 48 (98%) | 102 (88%) | 53 (44%) | 35 (15%) |
Medical History |
|||||
| Intrauterine Growth Restriction (IUGR) | 112 (22%) | 15 (31%) | 46 (40%) | 29 (24%) | 22 (9.4%) |
| Intraventricular Haemorrhage (IVH) | 24 (4.6%) | 16 (33%) | 7 (6.0%) | 0 (0%) | 1 (0.4%) |
| Retinopathy of Prematurity | 62 (12%) | 34 (69%) | 27 (23%) | 1 (0.8%) | 0 (0%) |
| Congenital Cardiac Disease | 56 (11%) | 21 (43%) | 22 (19%) | 7 (5.8%) | 6 (2.6%) |
| Chronic Lung Disease | 98 (19%) | 44 (90%) | 45 (39%) | 6 (5.0%) | 3 (1.3%) |
| History of Apnoea (Any Aetiology) | 120 (23%) | 37 (76%) | 65 (56%) | 13 (11%) | 5 (2.1%) |
| History of Invasive Ventilation | 104 (20%) | 40 (82%) | 48 (41%) | 8 (6.6%) | 8 (3.4%) |
| Respiratory Support at Surgery | 49 (9.4%) | 27 (55%) | 17 (15%) | 4 (3.3%) | 1 (0.4%) |
| History of Caffeine Use | 122 (23%) | 36 (73%) | 76 (66%) | 10 (8.3%) | 0 (0%) |
| 1 n; Median (Q1, Q3); n (%) |
|||||
Retrospective Cohort Study of Outcomes for Neonates and Infants Undergoing Inguinal Hernia Surgery at Multiple Australian and New Zealand Hospitals: The RetroNeo Study.
Statistical Analysis
1 Introduction
This is the statistical analysis that accompanies the RetroNeo study, which examines the anaesthetic techniques and perioperative outcomes of neonates and infants undergoing inguinal hernia surgery.
2 Results
2.1 Demographics
2.2 Surgical Details
Characteristic |
Overall |
Age Categories at Birth |
|||
|---|---|---|---|---|---|
≤ 27 Weeks |
28-32 Weeks |
33-36 Weeks |
≥36 Weeks |
||
| Number of Patients (N) | 519 | 48 | 116 | 122 | 233 |
| Post-Menstrual Age at Birth in Weeks (Median (IQR)) | 36.1 (31.4, 38.3) | 25.9 (24.5, 26.6) | 30.1 (28.7, 31.6) | 35.3 (34.0, 36.0) | 38.7 (38.0, 40.0) |
| Post-Menstrual Age at Surgery in Weeks (Median (IQR)) | 44.9 (41.4, 48.1) | 41.1 (39.2, 44.1) | 41.1 (38.4, 43.5) | 44.8 (41.9, 47.9) | 47.0 (44.9, 50.1) |
| Weight at Birth in Grams (Median (IQR)) | 2,140 (1,150, 2,998) | 731 (600, 910) | 1,203 (935, 1,650) | 2,109 (1,800, 2,540) | 3,130 (2,600, 3,450) |
| Weight at Surgery in Grams (Median (IQR)) | 4,200 (3,300, 5,205) | 3,565 (3,015, 3,990) | 3,108 (2,630, 3,700) | 3,960 (3,190, 5,115) | 4,900 (4,260, 5,600) |
| Type of Hernia Repair | |||||
| Bilateral | 218 (42%) | 31 (65%) | 71 (61%) | 47 (39%) | 69 (30%) |
| Unilateral | 301 (58%) | 17 (35%) | 45 (39%) | 75 (61%) | 164 (70%) |
| Surgical Approach | |||||
| Laparoscopic | 23 (4.4%) | 2 (4.2%) | 4 (3.4%) | 6 (4.9%) | 11 (4.7%) |
| Open | 496 (96%) | 46 (96%) | 112 (97%) | 116 (95%) | 222 (95%) |
| Incarcerated Hernia | 36 (6.9%) | 1 (2.1%) | 7 (6.0%) | 8 (6.6%) | 20 (8.6%) |
| Additional Associated Procedure | 55 (11%) | 8 (17%) | 12 (10%) | 13 (11%) | 22 (9.4%) |
| Total Duration in Minutes (Median (IQR)) | 74 (59, 94) | 97 (74, 122) | 79 (61, 103) | 73 (59, 88) | 70 (56, 85) |
| Anaesthetic Duration in Minutes (Median (IQR)) | 71 (55, 91) | 93 (70, 115) | 74 (57, 100) | 69 (53, 85) | 69 (54, 83) |
| Surgical Duration in Minutes (Median (IQR)) | 34 (25, 47) | 50 (36, 67) | 37 (28, 53) | 32 (22, 43) | 31 (25, 44) |
| 1 n; Median (Q1, Q3); n (%) |
|||||
2.3 Anaesthetic Details
2.3.1 General Anaesthesia
Characteristic |
Overall |
Age Categories at Birth |
|||
|---|---|---|---|---|---|
≤ 27 Weeks |
28-32 Weeks |
33-36 Weeks |
≥36 Weeks |
||
| Number of Patients (N) | 519 | 48 | 116 | 122 | 233 |
| Anaesthetic Type | |||||
| GA Only | 163 (33%) | 13 (28%) | 29 (27%) | 40 (34%) | 81 (36%) |
| Spinal Only | 77 (15%) | 7 (15%) | 27 (25%) | 22 (18%) | 21 (9.4%) |
| Caudal Only | 1 (0.2%) | 0 (0%) | 1 (0.9%) | 0 (0%) | 0 (0%) |
| GA + Spinal | 4 (0.8%) | 0 (0%) | 3 (2.8%) | 0 (0%) | 1 (0.4%) |
| GA + Caudal | 221 (44%) | 21 (46%) | 40 (37%) | 51 (43%) | 109 (49%) |
| GA + Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Spinal + Sedation | 8 (1.6%) | 2 (4.3%) | 2 (1.8%) | 1 (0.8%) | 3 (1.3%) |
| Caudal + Sedation | 18 (3.6%) | 3 (6.5%) | 5 (4.6%) | 5 (4.2%) | 5 (2.2%) |
| GA + Spinal + Caudal | 1 (0.2%) | 0 (0%) | 1 (0.9%) | 0 (0%) | 0 (0%) |
| GA + Caudal + Sedation | 5 (1.0%) | 0 (0%) | 1 (0.9%) | 0 (0%) | 4 (1.8%) |
| Type of GA | |||||
| Sevoflurane | 260 (50%) | 24 (50%) | 49 (42%) | 61 (50%) | 126 (54%) |
| Propofol | 7 (1.3%) | 0 (0%) | 2 (1.7%) | 3 (2.5%) | 2 (0.9%) |
| Sevoflurane + NO2 | 46 (8.9%) | 4 (8.3%) | 11 (9.5%) | 9 (7.4%) | 22 (9.4%) |
| Sevoflurane + Propofol | 82 (16%) | 5 (10%) | 12 (10%) | 16 (13%) | 49 (21%) |
| Sevoflurane + Dexmedetomidine | 6 (1.2%) | 0 (0%) | 1 (0.9%) | 3 (2.5%) | 2 (0.9%) |
| Sevoflurane + Propofol + Dexmedetomidine | 4 (0.8%) | 1 (2.1%) | 2 (1.7%) | 1 (0.8%) | 0 (0%) |
| Propofol + NO2 | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Propofol + Dexmedetomidine | 2 (0.4%) | 0 (0%) | 0 (0%) | 0 (0%) | 2 (0.9%) |
| None | 112 (22%) | 14 (29%) | 39 (34%) | 29 (24%) | 30 (13%) |
| Type of NMBA | |||||
| Rocuronium | 54 (10%) | 12 (25%) | 14 (12%) | 10 (8.2%) | 18 (7.7%) |
| Vecuronium | 58 (11%) | 6 (13%) | 14 (12%) | 11 (9.0%) | 27 (12%) |
| Atracurium | 92 (18%) | 8 (17%) | 18 (16%) | 23 (19%) | 43 (18%) |
| Cisatracurium | 19 (3.7%) | 1 (2.1%) | 5 (4.3%) | 7 (5.7%) | 6 (2.6%) |
| Suxamethonium | 5 (1.0%) | 0 (0%) | 1 (0.9%) | 1 (0.8%) | 3 (1.3%) |
| Suxamethonium + Rocuronium | 1 (0.2%) | 1 (2.1%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Suxamethonium + Vecuronium | 1 (0.2%) | 0 (0%) | 0 (0%) | 1 (0.8%) | 0 (0%) |
| Suxamethonium + Atracurium | 3 (0.6%) | 1 (2.1%) | 0 (0%) | 1 (0.8%) | 1 (0.4%) |
| Suxamethonium + Cisatracurium | 1 (0.2%) | 0 (0%) | 1 (0.9%) | 0 (0%) | 0 (0%) |
| None | 285 (55%) | 19 (40%) | 63 (54%) | 68 (56%) | 135 (58%) |
| NMBA Reversal Agent | |||||
| Sugammadex | 116 (22%) | 6 (13%) | 22 (19%) | 34 (28%) | 54 (23%) |
| Neostigmine | 65 (13%) | 10 (21%) | 15 (13%) | 14 (11%) | 26 (11%) |
| None | 338 (65%) | 32 (67%) | 79 (68%) | 74 (61%) | 153 (66%) |
| Paracetramol | 219 (42%) | 24 (50%) | 37 (32%) | 54 (44%) | 104 (45%) |
| Parecoxib | 7 (1.3%) | 0 (0%) | 0 (0%) | 3 (2.5%) | 4 (1.7%) |
| Opioid | 147 (28%) | 15 (31%) | 22 (19%) | 27 (22%) | 83 (36%) |
| Dexmedetomidine | 1 (0.2%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (0.4%) |
| Type of Airway | |||||
| ETT | 339 (65%) | 29 (60%) | 69 (59%) | 82 (67%) | 159 (68%) |
| LMA | 49 (9.4%) | 2 (4.2%) | 5 (4.3%) | 8 (6.6%) | 34 (15%) |
| Anaesthetic Face Mask | 6 (1.2%) | 1 (2.1%) | 1 (0.9%) | 1 (0.8%) | 3 (1.3%) |
| HFNP | 10 (1.9%) | 1 (2.1%) | 5 (4.3%) | 1 (0.8%) | 3 (1.3%) |
| Hudson Mask | 3 (0.6%) | 0 (0%) | 1 (0.9%) | 1 (0.8%) | 1 (0.4%) |
| LFNP | 19 (3.7%) | 8 (17%) | 3 (2.6%) | 5 (4.1%) | 3 (1.3%) |
| Guedel | 3 (0.6%) | 0 (0%) | 0 (0%) | 1 (0.8%) | 2 (0.9%) |
| Chin Support | 1 (0.2%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (0.4%) |
| None | 89 (17%) | 7 (15%) | 32 (28%) | 23 (19%) | 27 (12%) |
| 1 n; n (%) |
|||||
2.3.2 Spinal Anaesthesia
Characteristic |
Overall |
Age Categories at Birth |
|||
|---|---|---|---|---|---|
≤ 27 Weeks |
28-32 Weeks |
33-36 Weeks |
≥36 Weeks |
||
| Number of Patients (N) | 90 | 9 | 33 | 23 | 25 |
| Spinal Local Anaesthetic (Drug (Concentration)) | |||||
| Bupivacaine 0.25% | 2 (2.2%) | 1 (11%) | 1 (3.0%) | 0 (0%) | 0 (0%) |
| Bupivacaine 0.5% | 39 (43%) | 6 (67%) | 15 (45%) | 10 (43%) | 8 (32%) |
| Levobupivacaine 0.5% | 36 (40%) | 2 (22%) | 11 (33%) | 9 (39%) | 14 (56%) |
| Levobupivacaine 0.7% | 1 (1.1%) | 0 (0%) | 1 (3.0%) | 0 (0%) | 0 (0%) |
| Ropivacaine 0.2% | 1 (1.1%) | 0 (0%) | 1 (3.0%) | 0 (0%) | 0 (0%) |
| None | 11 (12%) | 0 (0%) | 4 (12%) | 4 (17%) | 3 (12%) |
| Number of Attempts | |||||
| 1 | 56 (64%) | 6 (67%) | 21 (64%) | 14 (64%) | 15 (63%) |
| 2 | 20 (23%) | 1 (11%) | 7 (21%) | 5 (23%) | 7 (29%) |
| 3 | 8 (9.1%) | 2 (22%) | 4 (12%) | 1 (4.5%) | 1 (4.2%) |
| 4 | 4 (4.5%) | 0 (0%) | 1 (3.0%) | 2 (9.1%) | 1 (4.2%) |
| Complications | |||||
| Bleeding | 1 (4.2%) | 0 (NA%) | 0 (0%) | 1 (14%) | 0 (0%) |
| Failed Attempt | 15 (63%) | 0 (NA%) | 7 (64%) | 3 (43%) | 5 (83%) |
| Inadequate Block | 5 (21%) | 0 (NA%) | 2 (18%) | 2 (29%) | 1 (17%) |
| Inadequate Block Duration | 2 (8.3%) | 0 (NA%) | 2 (18%) | 0 (0%) | 0 (0%) |
| Inadequate Surgical Conditions | 1 (4.2%) | 0 (NA%) | 0 (0%) | 1 (14%) | 0 (0%) |
| Conversion to GA | 22 (24%) | 1 (11%) | 9 (27%) | 5 (22%) | 7 (28%) |
| Adjuvant Sedation Used | 8 (8.9%) | 2 (22%) | 2 (6.1%) | 1 (4.3%) | 3 (12%) |
| Propofol Sedation | 1 (1.1%) | 0 (0%) | 0 (0%) | 1 (4.3%) | 0 (0%) |
| Dexmedetomidine Sedation | 1 (1.1%) | 1 (11%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Midazolam Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Clonidine Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Remifentanil | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Ketamine Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| NO2 Sedation | 2 (2.2%) | 0 (0%) | 2 (6.1%) | 0 (0%) | 0 (0%) |
| Sucrose Sedation | 4 (4.4%) | 1 (11%) | 0 (0%) | 0 (0%) | 3 (12%) |
| Type of Airway | |||||
| ETT | 1 (1.1%) | 0 (0%) | 1 (3.0%) | 0 (0%) | 0 (0%) |
| LMA | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Anaesthetic Face Mask | 2 (2.2%) | 0 (0%) | 1 (3.0%) | 0 (0%) | 1 (4.0%) |
| HFNP | 2 (2.2%) | 0 (0%) | 2 (6.1%) | 0 (0%) | 0 (0%) |
| Hudson Mask | 1 (1.1%) | 0 (0%) | 0 (0%) | 1 (4.3%) | 0 (0%) |
| LFNP | 8 (8.9%) | 5 (56%) | 1 (3.0%) | 1 (4.3%) | 1 (4.0%) |
| Guedel | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Chin Support | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| None | 76 (84%) | 4 (44%) | 28 (85%) | 21 (91%) | 23 (92%) |
| 1 n; n (%) |
|||||
2.3.3 Caudal Anaesthesia
Characteristic |
Overall |
Age Categories at Birth |
|||
|---|---|---|---|---|---|
≤ 27 Weeks |
28-32 Weeks |
33-36 Weeks |
≥36 Weeks |
||
| Number of Patients (N) | 246 | 24 | 48 | 56 | 118 |
| Spinal Local Anaesthetic (Drug (Concentration)) | |||||
| Bupivacaine 0.25% | 27 (11%) | 4 (17%) | 6 (13%) | 5 (8.9%) | 12 (10%) |
| Bupivacaine 0.5% | 1 (0.4%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (0.9%) |
| Levobupivacaine 0.2% | 3 (1.2%) | 0 (0%) | 1 (2.1%) | 1 (1.8%) | 1 (0.9%) |
| Levobupivacaine 0.25% | 43 (18%) | 3 (13%) | 4 (8.5%) | 13 (23%) | 23 (20%) |
| Ropivacaine 0.1% | 1 (0.4%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (0.9%) |
| Ropivacaine 0.2% | 159 (65%) | 16 (67%) | 34 (72%) | 36 (64%) | 73 (63%) |
| Ropivacaine 0.3% | 1 (0.4%) | 0 (0%) | 1 (2.1%) | 0 (0%) | 0 (0%) |
| None | 8 (3.3%) | 1 (4.2%) | 1 (2.1%) | 1 (1.8%) | 5 (4.3%) |
| Caudal Additives | |||||
| Adrenaline | 15 (42%) | 3 (60%) | 2 (40%) | 3 (33%) | 7 (41%) |
| Clonidine | 18 (50%) | 1 (20%) | 3 (60%) | 5 (56%) | 9 (53%) |
| Dexmedetomidine | 1 (2.8%) | 1 (20%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Saline | 2 (5.6%) | 0 (0%) | 0 (0%) | 1 (11%) | 1 (5.9%) |
| Number of Attempts | |||||
| 1 | 191 (79%) | 20 (83%) | 39 (81%) | 39 (71%) | 93 (82%) |
| 2 | 39 (16%) | 2 (8.3%) | 9 (19%) | 12 (22%) | 16 (14%) |
| 3 | 9 (3.7%) | 1 (4.2%) | 0 (0%) | 4 (7.3%) | 4 (3.5%) |
| 4 | 2 (0.8%) | 1 (4.2%) | 0 (0%) | 0 (0%) | 1 (0.9%) |
| Complications | |||||
| Failed Attempt | 10 (100%) | 3 (100%) | 0 (NA%) | 4 (100%) | 3 (100%) |
| Conversion to GA | 3 (1.2%) | 1 (4.2%) | 0 (0%) | 1 (1.8%) | 1 (0.8%) |
| Adjuvant Sedation Used | 23 (9.3%) | 3 (13%) | 6 (13%) | 5 (8.9%) | 9 (7.6%) |
| Propofol Sedation | 15 (6.1%) | 2 (8.3%) | 4 (8.3%) | 3 (5.4%) | 6 (5.1%) |
| Dexmedetomidine Sedation | 17 (6.9%) | 3 (13%) | 5 (10%) | 4 (7.1%) | 5 (4.2%) |
| Midazolam Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Clonidine Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Remifentanil | 1 (0.4%) | 1 (4.2%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Ketamine Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| NO2 Sedation | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
| Sucrose Sedation | 1 (0.4%) | 0 (0%) | 0 (0%) | 1 (1.8%) | 0 (0%) |
| Type of Airway | |||||
| ETT | 172 (70%) | 15 (63%) | 37 (77%) | 43 (77%) | 77 (65%) |
| LMA | 38 (15%) | 2 (8.3%) | 4 (8.3%) | 5 (8.9%) | 27 (23%) |
| Anaesthetic Face Mask | 4 (1.6%) | 1 (4.2%) | 0 (0%) | 1 (1.8%) | 2 (1.7%) |
| HFNP | 8 (3.3%) | 1 (4.2%) | 3 (6.3%) | 1 (1.8%) | 3 (2.5%) |
| Hudson Mask | 2 (0.8%) | 0 (0%) | 1 (2.1%) | 0 (0%) | 1 (0.8%) |
| LFNP | 11 (4.5%) | 3 (13%) | 2 (4.2%) | 4 (7.1%) | 2 (1.7%) |
| Guedel | 2 (0.8%) | 0 (0%) | 0 (0%) | 1 (1.8%) | 1 (0.8%) |
| Chin Support | 1 (0.4%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (0.8%) |
| None | 8 (3.3%) | 2 (8.3%) | 1 (2.1%) | 1 (1.8%) | 4 (3.4%) |
| 1 n; n (%) |
|||||